/**
 * Created with IntelliJ IDEA.
 * Description:
 * User: 黎鹤舞
 * Date: 2025-03-12
 * Time: 20:09
 */

/**
 *  809*??=800*??+9*??
 *  其中??代表的两位数, 809*??为四位数，
 *  8*??的结果为两位数，9*??的结果为3位数。
 *  求??代表的两位数，及809*??后的结果。
 */
public class EquationSolver {

    public static void main(String[] args) {
        for (int num = 10; num < 100; num++) {
            int left = 809 * num;
            int right = 800 * num + 9 * num;
            if (left == right) {
                boolean condition1 = (left >= 1000 && left < 10000);
                boolean condition2 = (8 * num >= 10 && 8 * num < 100);
                boolean condition3 = (9 * num >= 100 && 9 * num < 1000);
                if (condition1 && condition2 && condition3) {
                    System.out.println("??=" + num + ", 809*??=" + left);
                }
            }
        }
    }
}
